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      <a id="prealloc"></a>
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      <a id="IndexPrealloc" class="indexterm"></a>
      <div class="refnamediv">
        <h2>
          <span class="refentrytitle">prealloc</span>
        </h2>
        <p>prealloc — 
      Creates space for instruments but does not run them.
          </p>
      </div>
      <div class="refsect1">
        <a id="idp135542944"></a>
        <h2>Description</h2>
        <p>
      Creates space for instruments but does not run them.
    </p>
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      <div class="refsect1">
        <a id="idp135544304"></a>
        <h2>Syntax</h2>
        <pre class="synopsis"><span class="command"><strong>prealloc</strong></span> insnum, icount</pre>
        <pre class="synopsis"><span class="command"><strong>prealloc</strong></span> "insname", icount</pre>
      </div>
      <div class="refsect1">
        <a id="idp135547648"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>insnum</em></span> -- instrument number
    </p>
        <p>
      <span class="emphasis"><em>icount</em></span> -- number of instrument allocations
    </p>
        <p>
      <span class="emphasis"><em><span class="quote">“<span class="quote">insname</span>”</span></em></span> -- A string (in double-quotes) representing a named instrument.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp135616112"></a>
        <h2>Performance</h2>
        <p>
      All instances of <span class="emphasis"><em>prealloc</em></span> must be defined in the header section, not in the instrument body.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp135617904"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the prealloc opcode. It uses the file <a class="ulink" href="examples/prealloc.csd" target="_top"><em class="citetitle">prealloc.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp135619680"></a>
          <p class="title">
            <strong>Example 647. Example of the prealloc opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
<span class="comment">; Audio out   Audio in    No messages</span>
-odac           -iadc     -d     <span class="comment">;;;RT audio I/O</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o prealloc.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="comment">; Initialize the global variables.</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">kr</span> <span class="op">=</span> 4410
<span class="ohdr">ksmps</span> <span class="op">=</span> 10
<span class="ohdr">nchnls</span> <span class="op">=</span> 1

<span class="comment">; Pre-allocate memory for five instances of Instrument #1.</span>
<span class="opc">prealloc</span> 1, 5
 
<span class="comment">; Instrument #1</span>
<span class="oblock">instr</span> 1
  <span class="comment">; Generate a waveform, get the cycles per second from the 4th p-field.</span>
  a1 <span class="opc">oscil</span> 6500, p4, 1
  <span class="opc">out</span> a1
<span class="oblock">endin</span>


<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="comment">; Just generate a nice, ordinary sine wave.</span>
<span class="stamnt">f</span> 1 0 32768 10 1

<span class="comment">; Play five instances of Instrument #1 for one second.</span>
<span class="comment">; Note that 4th p-field contains cycles per second.</span>
<span class="stamnt">i</span> 1 0 1 220
<span class="stamnt">i</span> 1 0 1 440
<span class="stamnt">i</span> 1 0 1 880
<span class="stamnt">i</span> 1 0 1 1320
<span class="stamnt">i</span> 1 0 1 1760
<span class="stamnt">e</span>


<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />
    </p>
      </div>
      <div class="refsect1">
        <a id="idp135624000"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="cpuprc.html" title="cpuprc"><em class="citetitle">cpuprc</em></a>, <a class="link" href="maxalloc.html" title="maxalloc"><em class="citetitle">maxalloc</em></a>
    </p>
      </div>
      <div class="refsect1">
        <a id="idp135627040"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: Gabriel Maldonado</td>
          </tr>
          <tr>
            <td>Italy</td>
          </tr>
          <tr>
            <td>July 1999</td>
          </tr>
        </table>
        <p>
    </p>
        <p>Example written by Kevin Conder.</p>
        <p>New in Csound version 3.57</p>
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